Paper-feed mechanism for printing machines, having improved means for tensioning and positioning paper



Sept. 8, 1964 J. KONKEL 3,147,900

PAPER-FEED E HA M PRINTING MACHINES, HAVING ROV ME FOR T IONING AND POSITIONING ER Filed Sept. 19, 1962 3 Sheets-Sheet 1 'INVENTOR.

3,147,900 S, HAVING 5 Sheets-Sheet 2 J. KONKEL M FOR PRINTING MACHINE IMPROVED MEANS FOR TENSIONING AND POSITIONING PAPER Sept. 8, 1964 PAPER-FEED MECHANIS Filed Sept. 19, 1962 33mm ,QWZUL BY 5 7 ,Q Maid A TORNEYS Sept. 8, 1964 KQNKEL 3,147,900

PAPER-FEED MECHANISM FOR PRINT G MACHINES, HAVING IMPROVED MEANS FOR NSIONING AND POSITIONING PAPER Filed Sept. 19, 1962 3 Sheets-Sheet 5 FIG. 4

I N VB NTOR. rat/J4 KMLIL A TORNEYS United States Patent 3,147,900 PAPER-FEED MECHANISM FOR PRENTING MA- CHINES, HAVING IMPROVED MEANS FOR TEN- SEQNING AND POSHTIQNING PAIER Joseph Konlrel, Wakefield, Mass, assignor to Anelex Corporation, Boston, Mass a corporation of New Hampshire Filed Sept. 19, I962, Ser. No. 224,750 4 (Iiaims. (Cl. 226111) This invention pertains to paper-feed mechanisms for printing machines, and more particularly relates to an improved paper-feed mechanism having means for tensioning and positioning a length of paper for printing thereon. The invention has particular utility in the printing of prepared forms supplied in rolls of indeterminate length, but its usefulness is not limited thereto.

In machines of the type to which the invention particularly relates, a roll of paper forms is engaged over two feed spindles spaced apart longitudinally of the roll, one being positively driven by the other to feed a section of the roll forwardly in a predetermined plane path for printing. The roll may comprise a series of blank forms of predetermined length, each separable from the roll after printing. The printing mechanism is arranged to impress desired characters on the form over the span between the feed spindles, and may, for example, comprise a rotatable print wheel bearing a font of characters adjacent one surface of the paper, together with hammers positioned adjacent the opposite surface of the paper for impressing the paper against a selected succession of characters of the print wheel.

In order to produce satisfactory print impressions on the paper, particularly in high-speed printing, it is necessary to maintain the span of the paper roll between the feed spindles under a predetermined tension, and to this end the invention contemplates the adjustment of the angular relationship between the spindles. The spindles are positively drivingly interconnected by an endless belt, and it is a feature of the invention that adjustment in paper tension may be achieved without materially affecting the tension in the belt.

Rolled paper forms are frequently pre-printed with lines and perhaps with additional indicia, and it is necessary to obtain correct alignment between the pro-printed material and additional printed matter to be applied by a printing machine. However, tolerances in the manufacture of rolled forms, and variations in length caused principally by varying humidity conditions, may cause the forms to fail to register correctly with the printing apparatus unless some means are provided for adjusting the forms longitudinally with respect to the feed spindles. According to another feature of the invention, provision is also made for adjusting the angular position of both feed spindles jointly and equally to position a roll of forms with respect to the printing mechanism, Without varying the adjusted tension in the roll.

Further objects and advantages of the invention will become apparent from the following description of a preferred embodiment thereof, referring to the accompanying drawings, in which:

FIG. 1 is a fragmentary view in end elevation of a printing machine according to the invention;

FIG. 2 is a fragmentary view of a portion of the machine of FIG. 1, schematically illustrating paper tension adjusting means thereof;

FIG. 3 is a sectional view taken along line 33 in FIG. 1, looking in the direction of the arrows; and

FIG. 4 is a sectional end view taken along line 44 in FIG. 3, looking in the direction of the arrows.

Referring to the drawings, the improved paper-feed mechanism is shown in a preferred embodiment in a highspeed printing machine, which includes frame members 1th and 12 forming a rigid housing with a base plate 14 and a face plate 16, the latter having a frontal opening for insertion of a roll of paper forms 20 into the machine. Each form is illustratively shown as being separable from the roll along lateral perforations 21. The machine includes a pair of splined paper-feed spindles 22 and 24, each having a pair of drive sprockets 26 secured thereon in longitudinally-spaced relation, as by means of set screws 28. Each of the sprockets 26 has a circumferential row of pins 30 projecting therefrom for conformably engaging in rows of drive openings 32 pre-punched along the lateral edges of the roll, so that the paper is positively driven without slippage. Slotted guides 33 and 34 overlie the sprockets loosely to prevent the paper from slipping off the pins 30.

The roll 26 passes over the feed spindle 22 to a guide plate 35 (FIG. 4) having a transverse opening 36 therein, and thence to the feed spindle 24. In passing over the opening 36, the paper is received between a rotatable print wheel 38 having about its circumference a font of characters (not shown), and a series of hammers diagrammatically indicated at 49 (FIG. 4). The print wheel 33 is received within a stationary annular housing 42, which is formed with an arcuate opening 4-4 to expose the print wheel to the paper. A printing ribbon 4-6 extends between two take-up reels 48 about the housing 42, and thus intermediate the print wheel and the paper. In operation, the feed spindles drive the paper intermittently, pausing for printing each successive line. The print hammers 46 are actuated by automatic control means (not shown) in synchronism with the rotation of the print wheel 38 to impress desired characters on the paper in sequence; the hammers being actuated and supported by a hammer module mounting plate 50 pivotally supported in each frame 10 and 12 of the housing by a bracket 52 and a pivot pin 54, and secured in pre-adjusted position by means of a crank arm 56 mounted on a stub shaft 58. The print wheel 38 is rotatably supported in bearing means 6% and 62, mounted in the frame members 10 and 12, respectively, and is driven by a suitable motor 64, a flexible belt 66, and a sheave 63 secured to the print wheel. The printing mechanism in itself forms no part of the present invention, and further detailed description is believed unnecessary; this and alternative forms are known to those skilled in the art.

For driving the paper-feed spindles 22 and 24 intermittently, various drive means may be utilized. In the form shown, the motor 64 drives a clutch fly-wheel 7th by means of a flexible belt 72, and driving connection is made with the spindle 22 by means of an electromagnetic clutch generally designated 74. The clutch is engaged only when it is desired to advance the roll 20, and an electromagnetic brake generally designated 76 is provided to halt the rotation of the feed spindles during the printing operation. Suitable electric circuit means (not shown) are provided for alternatively actuating the clutch '74 or the brake 7 6 in synchronism with the operation of the printing mechanism, and under a common control; it should be understood that the brake is to be engaged, mechanically or electrically or both, at all times when the roll is not being fed forwardly by means of the clutch, thus to prevent any slippage of the paper as it is printed.

The clutch 74 is mounted in the frame 1% within a stationary housing 78, and includes a coil 80 carried within a ferromagnetic field structure 82, for establishing a closed toroidal flux path for the electromagnetic field. A clutch rotor 84 is secured to the fly-wheel 70 by means of a stub shaft 86, secured by a washer 88 and a screw 89. The rotor assembly is rotatably mounted in the field structure 82 by suitable bearings 90, coaxially with the spindle 22, which is mounted for independent rotation in the clutch housing '78 by means of bearings 92. Splined at the end of the spindle 22 for axial sliding movement thereon is a clutch disc 94 which, upon energization of the clutch, is drawn to the left as viewed in FIG. 3, into driving engagement with a friction ring 96 mounted in the face of the clutch disc 94. A dished spring 98 is arranged on the spindle to bias the clutch disc 94 lightly against the rotor 84- at all times, in order to minimize the lag in clutch engagement, while permitting the rotor to rotate freely at such times as the spindle 22 is braked.

The brake '76 is organized within a brake housing 160, which is itself rotatably received within an opening 102 in the frame member 12, being axially located by means of an undercut ring 164 secured to the frame 12 by means of screws 166. The housing 100 is secured in an adjusted angular position with respect to the frame 12 by means of an adjustable linkage generally designated at 1%, which includes a stud 111i threaded into the housing, a link 112 received on the stud, and a control rod 114- threaded into the link 11.2, and having an adjustment knob 116 secured thereto and rotatably supported through an opening in the face plate 16 for manual adjustment of the position of paper forms, in a manner which will later be described.

The brake includes a coil 11% supported within a ferromagnetic field structure 120 forming a toroidal flux path through a brake disc 122. A cover plate 123 encloses the field structure 120 and is secured on the housing 100 to enclose the unit. The brake disc 122 is splined in axially-slidable relationship on the spindle 22 for engagement with a friction ring 124 set into the face of the field structure 120 upon energization of the coil 118. A dished spring 12 biases the brake disc 122 to the right as viewed in FIG. 3, lightly against the friction ring 124, so as to minimize the lag in actuation of the brake, but the engagement is of such moderate pressure as not to interfere with rotation of the spindle 22 when the clutch '74 is engaged.

The specific forms of clutch and brake mechanism are not critical to the practice of the invention, although the forms shown are preferred. It is only necessary that intermittent driving means and braking means be provided, and that the angular position of the brake housing or stator be adjustable with respect to the frame of the machine.

For driving the spindle 24, a cog wheel 123 is splined on the spindle 22, and drives a flexible endless belt 130; a second cog wheel 132 is mounted on the spindle 24 and is engaged by the belt 130 to be positively driven with the spindle 22. For providing signal pulses indicating the advancement of the spindles and the paper fed thereby, a pulse wheel 134 is splined at the end of the spindle 22, and the assembly is secured by a washer 136 and a machine screw 138 threaded into the spindle. The manner of establishing pulse signals by means of the wheel 134 is well known to those skilled in the art, and inasmuch as it is not material to the practice of the invention, no further detailed description is believed necessary.

The spindle 24 is mounted in the frames and 12 by means of suitable bearing units 140 and 142, respectively, for rotation on an axis parallel to that of the spindle 22. To permit preliminary adjustment of the angular position of the sprockets 26 mounted on the spindle 24 to conform to the holes 32 of the roll 20, whose position is determined by the angular position of the spindle 22, the cog wheel 132 is rotatably supported on an internally splined sleeve 144- which is received by the spindle 24. The cog wheel is secured on the sleeve 144 in adjusted angular position by means of a disc 1% and machine screws 14?, and the entire assembly is secured on the spindle 24 by means of a screw 150. By these means, precise adjustment of the relative angular relationship of the two spindles and their sprockets may be made in increments less than the angular pitch of the spline teeth.

For adjustment of the tension in the span of paper extending between the spindles, a pair of belt-tensioning abutments comprising rollers 152 are mounted upon a bracket 154 to engage the opposite spans of the belt 139 transversely. The rollers are mounted on eccentric hubs 155 secured adjustably in the bracket by screws 156. The bracket 154 is rotatably received upon the outer race of the bearing 142 for pivotal movement about the axis of the spindle 24. This movement is limited by means of a plurality of studs 157 received in the frame member 12, and having Belleville washers 158 acting against the bracket to eliminate play in the assembly. The studs 157 cooperate with elongated slots 160 arranged in the bracket arcuately about the axis of the spindle 24.

The angular position of the bracket 154 with respect to the frame 12 is adjustable by means of a linkage which includes a pin 162 pivotally securing a link 1% in the bracket, and a manual adjustment knob 168 rotatably mounted and axially restrained in a conventional manner in an opening in the face plate 16.

Operation In operation, a roll of forms is first positioned on the drive sprockets 26 of both splines, being overlain by the slotted guides 33 and 34- and passing over the guide plate 35 beneath the print Wheel 38. Before commencing the printing operation, the brake 76 is energized, and the paper tension is adjusted to a desired level by rotation of the knob 163. As will be seen by a comparison of FIGS. 1 and 2, the latter of which shows the bracket 154- and rollers 152 adjusted to an extreme clockwise position, this adjustment causes one span of the belt 136 to be tautened and the other to be correspondingly slackencd. The net effect of the small angular movement is to create no substantial change in the belt tension, but to cause the spindle 24 to rotate in one direction or another to change its angular relationship with the spindle 22, which is held by the brake and remains stationary. As illustrated in FIG. 2, adjusting rotation has taken place clockwise through an angle *y to produce a maximum tcnsioning of the paper. It will be apparent that rotation of the bracket 154 in the counterclockwise direction would produce a slackening of the span of paper extending between the spindles.

The position of the roll of forms 29 with respect to the print wheel 38 can be adjusted by means of the knob 116 to bring pre-printed lines or other indicia on the forms into proper alignment. Rotation of the knob 116, being carried on while the brake 76 is engaged, produces direct rotation of the brake housing 1% and the spindle 22, and equiangular rotation of the spindle 24 by means of the belt 139. The adjustments having been completed, the printing operation may proceed in a conventional fashion by alternate actuation of the clutch 74 to advance the forms over the feed spindles, and actuation of the brake 76 to halt this movement for printinig each successive line.

It will thus be apparent that the improved feed mechanism makes it possible to adjust the tension of the paper roll, and to align pre-printed indica thereof with the print wheel, in such a manner that these successive adjustments are independent of one another, and further do not materially alter the pre-set tension in the drive belt 130.

While a preferred embodiment of the invention has been described by Way of illustration, it will be apparent to those skilled in the art that various changes and modifications may be made without departing from the true spirit and scope of the invention, which is therefore intended to be defined in the appended claims without limitation to specific details of the foregoing embodiment.

What I claim is:

1. In a printing machine, a paper-feed mechanism comprising a frame, first and second spindles for engagement with a length of paper extending therebetween, said spindles being mounted in said frame for rotation about spaced-apart parallel axes, an endless belt drivingly interconnecting said spindles, means for driving said first spindle, disengageable means for braking said first spindle, said braking means comprising a brake rotor drivingly connected with said first spindle and a brake housing engageable with said rotor and rotatably mounted in said frame, first adjustable positioning means for securing said brake housing in a selected angular position with respect to said frame, such that the angular positions of said spindles with respect to said frame may be equally and jointly adjusted when said rotor and housing are engaged to position a length of paper engaged with said spindles, a bracket supported on said frame for rotation about the axis of said second spindle, second adjustable positioning means for securing said bracket in a selected angular position with respect to said frame, and a pair of belttensioning abutments mounted on said bracket for transversely engaging the opposite spans of said belt extending between said spindles to take up slack therein, such that the angular position of said second spindle with respect to said frame may be adjusted when said rotor and housing are engaged to vary the tension in said length of paper without altering the tension in said endless belt.

2, In a printing machine, a paper-feed mechanism comprising a frame, first and second spindles for engagement with a length of paper extending therebetween, said spindle being mounted in said frame for rotation about spaced-apart parallel first and second axes, respectively, an endless belt drivingly interconnecting said spindles, means for driving said first spindle, disengageable means for braking said first spindle, said braking means comprising a brake rotor drivingly connected with said spindle and a brake housing engageable with said rotor and mounted in said frame for rotation about said first axis, a first positioning linkage connecting said frame to said brake housing at a distance from said first axis, said first linkage being adjustable in length such that the angular positions of said spindles with respect to said frame may be equally and jointly adjusted when said rotor and housing are engaged to position a length of paper engaged with said spindles, a bracket supported on said frame for rotation about said second axis, a second positioning linkage connecting said frame to said bracket at a distance from said second axis, and a pair of belt-tensioning abutments mounted on said bracket for transversely engaging the opposite spans of said belt extending between said spindles to take up slack therein, said second linkage being adjustable in length such that the angular position of said second spindle with respect to said frame may be adjusted to vary the tension in said length of paper without altering the tension in said endless belt.

3. In a printing machine, a paper-feed mechanism comprising a frame, first and second spindles for engagement with a length of paper extending therebetween, said spindles being mounted in said frame for rotation about spaced-apart parallel axes, an endless belt drivingly interconnecting said spindles, means for driving said first spindle, disengageable means for braking said first spindle, said braking means comprising a brake rotor drivingly connected with said first spindle and a brake housing engageable with said rotor and rotatably mounted in said frame, and adjustable positioning means for securing said brake housing in a selected angular position with respect to said frame, such that the angular positions of said spindles with respect to said frame may be equally and jointly adjusted when said rotor and housing are engaged to position a length of paper engaged with said spindles.

4. In a printing machine, a paper-feed mechanism comprising a frame, first and second spindles for engagement with a length of paper extending therebetween, said spindles being mounted in said frame for rotation about spaced-apart parallel first and second axes, respectively, an endless belt drivingly interconnecting said spindles, means for driving said first spindle, disengageable means for braking said first spindle, said braking means comprising a brake rotor drivingly connected with said first spindle and a brake housing engageable with said rotor and mounted in said frame for rotation about said first axis, a positioning linkage connecting said frame to said brake housing at a distance from said first axis, said linkage being adjustable in length such that the angular positions of said spindles with respect to said frame may be equally and jointly adjusted When said rotor and housing are engaged to position a length of paper engaged with said spindles.

References Cited in the file of this patent UNITED STATES PATENTS 2,347,900 Frazer-Nash et al May 2, 1944 3,049,276 Wilkins Aug. 14, 1962 

3. IN A PRINTING MACHINE, A PAPER-FEED MECHANISM COMPRISING A FRAME, FIRST AND SECOND SPINDLES FOR ENGAGEMENT WITH A LENGTH OF PAPER EXTENDING THEREBETWEEN, SAID SPINDLES BEING MOUNTED IN SAID FRAME FOR ROTATION ABOUT SPACED-APART PARALLEL AXES, AN ENDLESS BELT DRIVINGLY INTERCONNECTING SAID SPINDLES, MEANS FOR DRIVING SAID FIRST SPINDLE, DISENGAGEABLE MEANS FOR BRAKING SAID FIRST SPINDLE, SAID BRAKING MEANS COMPRISING A BRAKE ROTOR DRIVINGLY CONNECTED WITH SAID FIRST SPINDLE AND A BRAKE HOUSING ENGAGEABLE WITH SAID ROTOR AND ROTATABLY MOUNTED IN SAID FRAME, AND ADJUSTABLE POSITIONING MEANS FOR SECURING SAID BRAKE HOUSING IN A SELECTED ANGULAR POSITION WITH RESPECT TO SAID FRAME, SUCH THAT THE ANGULAR POSITIONS OF SAID SPINDLES WITH RESPECT TO SAID FRAME MAY BE EQUALLY AND JOINTLY ADJUSTED WHEN SAID ROTOR AND HOUSING ARE ENGAGED TO POSITION A LENGTH OF PAPER ENGAGED WITH SAID SPINDLES. 